Control device



Dec. 25,- 1934. v w. L. HlcKsTElN Er AL 1,985,659

CONTROL DEVICE Filed Deo. 12, 1930 fz /j //zz 27 WZ, a

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Patented Dec.4 25, 1934 UNITED sTAEs PATEN GCNTRTL DEWCE William L.ckstein, Hrvington, and Edwin CU.,

Loesser, Glen Ridge, N. d.

26 Claims.

This invention relates to control devices which may govern mechanism o1any type. 1n the particular embodiment we have illustrated the inventionis applied to an oil burning steam heater 5 as our rst commercialdevices were used in con- 4 tion is to provide a. device that willoperate in some :fashion entirely automatically and in respense toeither of two movements substantially at right angles to each other orto the combined movements. the present invention is the provision o anautomatic switch which will be operated by a horizontal movement of thecontrol device to open or close the switch and in addition will beoperated to open or close the device independently of the rst movementif the control rod be moved in a different direction.

A still further object of the present invention lies in the provision ofan automatic device for control of the motor of an oil burner by eitherchange in pressure or change in water level or both.

In many installations it is common to cut off the heat when the steampressure or the temperature reaches some chosen maximum point and toturn on the heat either by moving a valve or starting a. motor when somechosen minimum is reached and the. installation generally contains inaddition a separate switch which closes the valve or stops the motorWhenever the water level sinks below a certain chosen point. While thetwo devices Working together are very common there is no simple compactautomatic control unit for accomplishing both purposes.

In the drawing:

Figure 1 is a side elevation partly broken away.

Figure 2 is an end view of the preferred apparatus as shown in Figure 1but with the ca removed.

Figure 3 is a side elevation of a modied form.

Figure 4 is a still further modification.

Figure 5 is an end view of the switch cradle.

Figure 6 is a plan of the contact members shown in Figure d.

in. the preferred form shown in Figures l and 2, the device consists ina casting lo having a steamy A second and important object of j iT [l .Y1 i. Application necesite@ le, ieee. seein ne. coince niet *i "u i 1(Cle 2Min-Stell inlet nipple il and a water inlet 12, the former incommunication with the steam chamber of the boiler and the latter incommunication with the water which. is being heated. The pressure in thechamber i3 will, therefore, be the same as the pressure in the steamline and the entire device is so located that the chosen water level isat the longitudinal center line ci the cylindrical castlli.

To the open end ci" the casting l is secured a dish lei permanentlycarrying a corrugated metal cylinder l hereinafter called the bellows.The circular end i6 of the bellows is preferably oi slightly heaviermetal than the corrugated portion and this dislf. carries centrally abearing and carries near its periphery a float 18. While obviously the`doat 18 may be spaced away from the bellows as in earlier models, Weiind it convenient 'to build the bellows in the short test tube icrmlustrated and to fasten it securely and permanently to the bellows andalso the rod 20 which slides freely but rather snugly 'thru the bearingl?.

From the .above it will be seen that the chamber i3 is uid and liquidtight and that when the steam pressure entering thru port 1l increasesthe bellows will be made shorter and since the bellows carries the floatand the rod 2G is attached to the oat at its far end any increase oipressure will move the rod 26 in an axial direction and any decrease inpressure, augmented, if desired, by the optional helical spring 2l whichwe rind unnecessary with the rather low pressure encountered in oilburning heaters, the rod 20 is moved horizontal to the right as seen inFigure l. A further and totally independent movement ot the rod followschanges in the water level. As illustrated the Water level is at thedesired height. Should the water level sink in the main device the waterlevel in chamber i3 would respond at once and the float 20 would fallbut since the bellows is fast to the-closure disk lli the rod 2O willturn about the bearing 1'? which acts as a ulcrum. The bellows, beingreadily bendable, will permit the necessary tilting of the end wall loas will readily be understood by those familiar with these elements. itwill thus be seen that the central rod 20 will move axially in responseto pressure changes and will tilt about some central point in responseto water level changes.

in the preferred form the object which is controlled by movement of therod is an electric maire and break apparatus of the mercury type knownin the trade as a mercoid switch. This tube is given the numeral 22 andreceives its currents thru wires 23 leading to ari-outlet box 24. Whilethe tube itself is of well-known commercial form its mounting is novel.lThe removable end wall 14 ol. the pressure chamber carries the outletbox at the bottom and two parallel brackets 25, the free ends of whichare con' nected by a pivot rod 26 on which is swung a cradle 27 which ismerely a strap of material preferably spring metal to embrace ratheriirmly the tiltable mercoid tube 22. At each side and diametrically ofthe tube is an outwardly Aextending lug 28 positioned so as to beengaged by a rather heavy wire frame 30 adjustably carried on thecontrol rod 20. We prefer to have the engagement between the lug 28 andthe frame 30 adjustable because in this way we can use the same devicefor many differentA types of installation. A very convenient way of.achieving this purpose is by having a portion of the control rodi- 20threaded and on this threaded portion we locate a nut 31 having anextended sleeve 32 which is annularly grooved to receive the nearlycircular end 33 of the fork frame 30. The frame being of spring steelcan be adjusted manually after the nut is correctly set so as not toengage either the tube or .the sides of the cradle 27 and preferably thenut 3l should be held in chosen position by some positive means such asthe lock nut 34. Upon decrease of pressure in the chamber 13 the rod 20moves to the right and the space between the lug 28 andthe verticallystanding arms of"l the fork 30 increases.

` When, however, the pressure increases within the in the left hand endand the pressure breaks the electric current4 which in this case goestothe P motor and the stopping of the motor in turn cuts off the supplyof liquid fuel. When the pressure or temperature decreases the bellows15 expands and the current is again completed to the motor.

The same mercury tube 22 responds independently to a change in waterlevel. The control rod 20 at its extreme left hand edge is bent upwardlyas at 36. We do not ilnd it necessary to fork this end but the roundedfree end strikes the tube at its lowest point and with pressure changesmerely slides horizontal on the tube having no eiect whatsoever upon it.Should the water level drop, however, the end 36 of the control rod iselevated and this tilts-the mercury tube 22 in exactly the same way asdoes the engagement between the frame 30 and the lugs 28. It will benoted that the upturned end 36 of the control rod also acts as a stopfor the switch. Except for this provision it would be necessary to havesome means for preventing the heavier left hand end of the tube movingdownwardly.

In Figure 3 the casing is made in two parts 10u and 10b binding betweenthem in fluid tight manner a circularly corrugated disk 40 to which thecontrol rod 20a is permanently secured. The

oat 18 in this case is spaced from the diafragm disk 40 but theoperating mechanism in the left hand space is identical and, as in thepreferred form, it is covered by a readily removable light cap 41 whichmay, if desired, be of anecdote glass or other transparent material. InFigure 4 the mercury switch is replaced by a pair of spaced terminals 44which are bridged to complete the circuit by the upturned end 36b of thecontrol rod 20h. The frame 30 has its counterpart in a cam surface 45which presses two spring leaf terminals 44 downward into contact with anelectrically-conducting bridging member 46 carried on the control rodpreferably in an adjustable manner as by the nut 31h. In thismodincation the member 47 moves horizontally in accordance withsomechange in conditionsl as,for example, a change in pressure. The rodcarries a` plate. 48 which may engage a roller 49 on the control rodwhich is spring pressed against the plate 48 so as to move the controlrod horizontally against the spring. The member' 50 corresponds to thefloat and it moves vertically in accordance with some change inconditions as, for example, the water level. This member 50 ends in aring 51 which rather Asnugly embraces the control rod which slidesfreely in a spherical bearing 52 set in a wall 14". As in the othermodifications the circuit is completed or is broken as may be desiredupon a movement oi' the member 47 in one direction and by a movement ofthe member 50 in a vdirection at right angles to the movement of themember 47.

What we claim is:

l. A device operated by changes in water level and pressure, comprisinga float, a pressure responsive element secured to said float, meansactuated by the float in response to changes in liquid level, said meanslsoconnected to the pressure responsive element as to be actuatedthereby independently of the liquid level changes.

2. In combination, a float, a pressure responsive device, an operatingelement, a mercury switch tube and a cradle therefor, said tube andcradle forming a pivoted crank of which the tube is the substantiallyhorizontal arm and the cradle is the substantially vertical arm, saidoperating element being pivotally supported by the pressureresponsivedevice and so connected to the float as tobe actuated bychanges in liquid level, the operating element being positioned to move4against the vertical arm of the suspended crank when actuated by thepressure responsive device, and positioned to move against thehorizontal tube when actuated about its pivot by the float.

3. A bellows and a iioat flxedly secured thereto in combination with arod to produce a movement of one end thereof in two directions normal toeach other.

4. A diafragm anda iloat in combination with one end of a rod to producea movement of the other end of the rod in two directions normal to eachother.

5. 'I'he combination with a member to operate a control device, ofactuating means to move the member in one direction in accordance with achanged condition, and a second actuating means xedly secured to saidfirst mentioned means to move the member at an angle to such directionin accordance with a different changed condition.

6. In a device for completing an electrical circuit, a rod, a bearing inwhich the rod' is slidably and pivotally supported, and means located onone side of said bearing moving substantially normally to each other formoving the rod in and about its bearing. f

7. In a pressure operated switch controllin device, a pivoted cradle, apressure responsive member, a rod connected to said member, a camadjustably secured on saidrod to tilt the cradle upon increase. ofpressure, and means at the end of the rod for holding the cradle athorizontal.

8. In combination, a cylindrical bellows expansible under pressure, ailoat secured to the bellows, and a rod fast to the iloat and passingaxially thru the bellows.

9. In combination, a corrugated metal pressure responsivecylinder'closed at one end by a disk, a perforated wall supporting thecylinder at the free end in fluid tight fashion, a rod passing thru thehole in the wall and passing axially thru the cylinder, and a floatsecured Ito the free end oi the rod.

10. In combination, a chamber adapted to be placed in communication witha iluid reservoir anda pressure system, a. pressure responsive diafragmclosing one side of said chamber, a inember pivoted to said diafragm anda float secured to the member and lying within the chamber.

ll. In a switch, a pair of contacts, a bridging member mounted to -ioinsaid contacts upon lowering of a water level, a second bridging inember,and pressure responsive ineans to cause the second bridging member toloin said contacts.

l2. in combination, a vessel having a steers port and a water port, e.float within said chainber, a pivoted lever carrying said oat, pressureresponsive means for moving the pivot ci the lever in a horizontaldirection, a tiltable member supported by the lever, and means fortranslating the sliding movement of the lever into tilting movement ofthe-member independently ci the support given the tilting member by therod.

is. in combination, a rod, adapted to open .and close an electricswitch, means responsive to pressure changes to move the rod, and d oatsecured to said rod to rnove the rod in response to changes in liquidlevel.

le. An electric switch, a rod, a pressure responsive member secured tosaid rod to move the rod axially to operate said switch, and a floatdirectly secured to said rod to operate said switch in accordance withliquid level changes.

15. A switch operating unit consisting of means responsive to liquidlevel changes and means responsive to pressure changes, and a switchengaging member rigidly secured to both of said means to move constantlytherewith.

i6. In combination, a member having a free end adapted to be operativelyconnected to a desired mechanism, activating meanslocated at a ilxeddistance from said free end and responsive to liquid level changes formoving the free end ci said member, and means responsive to pressurechanges to move the free end of the member, said first mentioned meansbeing so connected to said member as to maintain said xed distanceduring all changes in pressure and liquid level.

i7. In combination, a chamber having an opening in one wall, a pressureresponsive device sealing said chamber, a rod centrally pivoted in saiddevice, a float within the chamber and secured to one end of the rod,the free end of said rod extending thru said opening, a switch adjacentto said free end and adapted to be operated thereby upon movement of therod by pressure on. the device or by change in water level in sai'ichamber.

i8, A combined pressure and float actuated switch mechanism for boilers,comprising a casing having means for communicating with the interor of aboiler above and belowthe water level thereo, an electric switchmechanism including a mercury tube switch and operating means forthrowing the switch tube to open and closed posiiions, an expansible andcontractible member within the casing and connectedto said switchoperating means whereby a change of pressure in the casing actuates theswitch actuating means, in combination with means within the casingincluding e, float, said switch operating means connected to andcommunicating the movement of said oat to the exterior oi the casingwhereby changes in the water level in the boiler actuate the switch.

i9. in combination, a casing, an apertured closure on one end of thecasing, a pressure responsive bellows secured to said closure over saidaperture and extending within the casing, a float secured to the innerend of the bellows, a rod connected to the bellows and to the oat andextending thru said aperture and switch means mounted adjacent the freeend of the rod whereby movement ci the rod due to pressure change andwater level change or both operates said switch.

2li. lin combination, a cylindrical bellows havine e, closed end and anopen end, a float sealed to said closed end, a rod secured to saidclosed end, a water level casing having an apertured wail and ineens forsecuring said open end to said wail whereby the bellows, the float andthe rod are supported by the wall, said rod extending from said closedend axially thru the bellows and thru said wall and means mountedexterior oi said casing adapted to be operated by axial and transversemovement of the free end of said rod.

2l. il device operated by changes in water level and pressure,comprising e, pressure re sponsive element, float supported by saidelement, ineens actuated by the float in response to changes in liquidlevel, said means being hxediy secured to the pressure responsiveelement whereby chmees in pressure actuate said means independently cichange in liquid level.

22. in combination, a water level casing havin@ s. removable aperturedlwall, a pressure responsive bellows within the casing secured to thewall, a float secured to the bellows, a rod secured to the doet andthereby to the bellows and extending thru the aperturedV wall, and aswitch mounted on said casing adjacent the free end of said rod andadepted to be operated thereby.

23. d combined pressure and oat actuated switch mechanism for boilers,comprising a water level casing, a pressure responsive device and ai'loat within the casing, an electric switch mechanisrn including amercury switch tube suspended in a pivoted cradle, a unitary means formoving the tube into open and closed positions, said means beingconnected to the pressure responsive device and doet on the interior ofthe casing; whereby change in pressure or change in water level willactuate said switch.

24. A combined pressure and float actuated mechanism for boilers,comprising a casing provided with ineans for communicating with theinterior of s, boiler above and below the water level thereof, anelectric switch mechanism including a mercury switch tube pivotallysupported by said casing, unitary operating means for moving the switchtube into open and closed positions, a pressure responsive device of thebellows type secured to the inner wall of the casing and a float withinthe casing, said float and said device being connected together and tosaid switch operating means whereby either change in pressure or changein water level or both will move said operating means to actuate saidswitch.

25. In a. mercury tube switch having Ybut two moving parts, a support, acradle freely suspended on. a pivot in said support, a mercury tuberesilently clamped in said cradle and adapted to hang in a,substantially horizontal position below said pivot, a. pivoted rod,float means on one end of said rod for turning the same about its pivotto bring the free end thereof into engagement with said tube to therebyactuate the switch.

26. In a mercury tube switch, a support, a cradle freely suspended on apivot said support, a mercury tube resiliently clamped in said resuenacradle and adapted to hang in a substantially horizontal position belowsaid pivot, a pivoted rod, float means on one end of said rod forturning the same about its pivot to bring the free end thereof intoengagement with said tubewto thereby actuate the switch, means formoving said rod and its pivot longitudinally, and means on the EDWIN C.LOESSER. ILLIAM L. HICKBTEIN.

